Catlemur

Well I was thinking of making something more mainstream.I was thinking of a big continent surounded by the Great Ocean and a few island group around it (but we can still use a part of your idea:f.e. there once was a great tree rising from the ocean's deep that collapsed but it's top became the big cotinent.I am also going to use few mainstream races:the humans and gnomes (dwarfs).Your ideas about the bestiary?I have already created a short one. 

Thus there is a new continent as it were, of trees like a forest, their roots drawing the lifeforce of the fantasy world itself. When they die the canopy breaks off from its underwater trunk and it becomes a floating island with thousands of creatures of all types on it, raiding the coastlines of the fantasy world like vikings, until they come across another ocean tree, where upon a massive war is fought for control of the living tree, its diverse lifeforms fighting the invader lifeforms, magic and dragons and sea creatures and arboreal (tree dwelling) beasts of all types. A new continent as it were in the fantasy world

They stillexist in the same fantasy world, but in the Great Ocean. The idea revolves around giant trees that sprout from the bottom of the deppest ocean trenches, to sprout out a truly massive canopy on the waters surface. Each Ocean Tree can be ten miles tall from the bottom of the ocean to the top, the canopy up to two miles high into the sky, and ten or more miles in circumference, massive branches supporting a unique world of arboreal, flying, and ocean creatures. Each looks like a round island with a great circular mountain from afar. But infact they are massive old trees. Tens of thousands of years old. 

My ideas revolve around a new type of fantasy world that lives apart and relatively unknown by the mainstream fantasy world of elves and dwarves and the like.